The present invention relates to a disc drive microactuator system, and more particularly to an improved technique for electrically connecting a transducing head to a suspension flexure in the disc drive microactuator system.
The density of concentric data tracks on magnetic discs continues to increase (that is, the width of data tracks and radial spacing between data tracks are decreasing), requiring more precise radial positioning of the head. Conventionally, head positioning is accomplished by operating an actuator arm with a large-scale actuation motor, such as a voice coil motor, to radially position a head on a flexure at the end of the actuator arm. The large-scale motor lacks sufficient resolution to effectively accommodate high track-density discs. Thus, a high resolution head positioning mechanism, or microactuator, is necessary to accommodate the more densely spaced tracks.
One promising design for high resolution head positioning involves employing a high resolution microactuator in addition to the conventional lower resolution actuator motor, thereby effecting head positioning through dual-stage actuation. Various microactuator designs have been considered to accomplish high resolution head positioning. Mechanical assembly and electrical interconnection of head level microactuators requires accurate alignment of extremely small components. Current tool fixtures reference to the side of the slider, which adds the slider width tolerance to the positioning error when mounting the slider to the suspension. Referencing to the center of the part being aligned would be preferable, but would require entirely new tooling, at great cost.
In addition to alignment, problems with mechanically and electrically attaching the slider to the microactuator exist. If adhesives are used to bond the parts, a fixture must hold the parts in correct alignment until the adhesive cures, without the adhesive bonding the parts to the fixture. Current electrical interconnection technology (ultrasonic welding) requires that substantial forces be applied to the microactuator devices, which requires special support during welding to prevent breakage.
Further, the microactuator increases the complexity of manufacturing the head assembly because in addition to the electrical connections required between the head and suspension, electrical connections to the microactuator are also required. Electrical connections from the head bond pads to the microactuator rotor bond pads requires a third xe2x80x9cinterposerxe2x80x9d lead frame, which is bonded first to the slider bond pads before slider/microactuator assembly, and then to the microactuator bond pads after assembly.
Thus, there is a need in the art for an improved interconnect between the slider and microactuator to alleviate the above-described deficiencies in the current state of technology.
The present invention relates to connecting a slider to a microactuator. The microactuator has a slider cavity into which a slider is inserted. Overhanging the cavity are tabs made of a flexible material, such as metal, which are deformed as the slider is inserted into the cavity. The flexible tabs serve to align the slider in the slider cavity.
The flexible tabs also serve to create a mechanical connection between the slider and the microactuator. This mechanical connection may be strong enough to hold the slider permanently in place. Alternatively, the mechanical connection created by the deformed tabs may only serve to hold the slider in place during a more permanent bonding process. Finally, the flexible tabs may also be used to form an electrical connection between bond pads on the slider and traces on the microactuator. Solder may be used to affix the deformed tabs to the slider bond pads, creating a stronger mechanical connection and more reliable electrical connection.